Recovery of Critical Rare-Earth Elements Using ETS-10 Titanosilicate

Jun 13, 2019 - In this study, we demonstrate that ETS-10 (Engelhard Titanosilicate 10) is a ... (16,17) This Research Note therefore focuses on the ad...
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Research Note Cite This: Ind. Eng. Chem. Res. 2019, 58, 11121−11126

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Recovery of Critical Rare-Earth Elements Using ETS-10 Titanosilicate Jay Thakkar,† Blaine Wissler,† Nick Dudenas,† Xinyang Yin,† Madeline Vailhe,‡ John Bricker,§ and Xueyi Zhang*,† †

Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States § Franklin Towne Charter High School, Philadelphia, Pennsylvania 19137, United States Downloaded via UNIV OF NEW SOUTH WALES on August 27, 2019 at 01:02:04 (UTC). See https://pubs.acs.org/sharingguidelines for options on how to legitimately share published articles.

‡

S Supporting Information *

ABSTRACT: The present work deals with the recovery of critical rare-earth elements (REEs) from acidic aqueous solutions. In doing so, we study the adsorption of these ions on ETS-10 titanosilicate. The experimental data are individually fitted with the Langmuir and Freundlich isotherms, and a high adsorption capacity for REEs is found. We further explore the competitive separation of Nd3+ from Ni2+ ions and Dy3+ from Nd3+ ions usually found in aqueous streams generated during the recycling of NiMH batteries and NdFeB permanent magnets, respectively, via adsorption using ETS-10.

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exchange has been extensively studied;16,17 however, there have been very limited studies on the ion exchange of REE cations on inorganic microporous materials for the purpose of enriching REEs and separating REEs from each other. In this study, we demonstrate that ETS-10 (Engelhard Titanosilicate 10) is a microporous titanosilicate suitable for separating REE cations by ion exchange. ETS-10 is a 12member ring microporous titanosilicate that can be hydrothermally synthesized without using templates or fluoride ions.18,19 Its 3D porous framework contains 1D chains of TiO62− units, generating chains of ordered and exchangeable charge-balancing cations (Na+ and K+).16−18 Although there have been numerous attempts to utilize inorganic microporous materials for the adsorption of heavy metal cations, to the best of our knowledge, the adsorption capacity of ETS-10 for critical REE cations in acidic aqueous solutions at dilute metal concentrations has not been studied in detail.16,17 This Research Note therefore focuses on the adsorption of critical REE cationsY3+, Nd3+, Eu3+, Tb3+, and Dy3+on ETS-10. We found that the fitting parameters for the adsorption of these ions on ETS-10 are significantly different from each other, indicating that ETS-10 can be used to separate these ions from each other by adsorptive methods. We also further

INTRODUCTION Rare-earth elements (REEs) are indispensable in many advanced technical and energy applications, such as wind turbines, photovoltaics, fuel cells, electric vehicles, water treatment, and electronics.1−5 The worldwide demands for these REEs have surged over the past two decades. Because of the geographically uneven distribution of REEs, the recovery of REEs is an approach complementary to mining to maintain a sustainable supply. Permanent Nd magnets, lamps, and NiMH batteries are some of the key sources containing a large amount of recyclable REEs, where the recycling potential of critical REEsY, Nd, Eu, Tb, and Dy (the five critical REEs identified by the U.S. Department of Energy)from these sources is estimated to be 1615, 4755, 115, 121, and 330 tons, respectively, in 2020.1−4,6 On the basis of this optimistic projection, the recovery of REEs from aqueous waste solutions can be a promising approach to produce REEs from secondary sources. Ion exchange and solvent extraction are the two most common methods for separating REEs. A major advantage of ion exchange over solvent extraction is the lack of use and recycling of organic solvents or organic compounds.7 Various synthetic cation-exchange frameworks are being explored for their adsorption capabilities for the separation of REEs.1−3,8−17 Microporous titanosilicate materials are a type of inorganic material with ordered micropores used in wastewater treatment; the application of titanosilicate materials for cation © 2019 American Chemical Society

Received: May 12, 2019 Accepted: June 13, 2019 Published: June 13, 2019 11121

DOI: 10.1021/acs.iecr.9b02623 Ind. Eng. Chem. Res. 2019, 58, 11121−11126

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Industrial & Engineering Chemistry Research

(actual ratio: 11.93 ± 0.27). For convenience, we will write the desired metal ratios and not the actual ratios henceforth. Characterization. Powder XRD analysis was performed on as-synthesized and metal-adsorbed ETS-10 samples using Nifiltered Cu Kα radiation (λ = 1.54 Å) at 40 mA and 45 kV on a PANalytical Empryean diffractometer. N2 physical adsorption on as-synthesized ETS-10 degassed at 200 °C for 12 h was performed using an Micromeritics ASAP 2420 apparatus. FEI Talos F200X and Thermo Fisher Scios 2 apparatuses were used to obtain TEM, STEM-EDS, and SEM micrographs. The elemental analysis of the supernatant was performed by Galbraith Laboratories and the Laboratory for Isotopes and Metals in the Environment (LIME) at the Pennsylvania State University.

explored the competitive adsorption of Nd3+ and Ni2+ ions from Ni−Nd aqueous solutions usually generated during the recycling of NiMH batteries and the competitive adsorption of Dy3+ and Nd3+ ions from Nd−Dy aqueous solutions usually generated during the recycling of NdFeB permanent magnets using ETS-10. The results indicate that ETS-10 can be used to separate Nd3+ from Ni2+ ions and Dy3+ from Nd3+ ions.

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EXPERIMENTAL SECTION Chemicals. The following chemicals were utilized as obtained: NaOH (EMD Millipore, ≥99%), KOH (EMD Millipore, ≥84%), TiO2 (Acros Organics, P25), sodium silicate solution (Merck, Na2O (7.5−8.5%), SiO2 (25.5−28.5%)), HCl solution (Sigma-Aldrich, 37 wt %), Y(NO3)3·6H2O (Acros Organics, 99.9%), Nd(NO3)3·6H2O (Sigma-Aldrich, 99.9%), Eu(NO3)3·6H2O (Alfa Aesar, 99.9%), Tb(NO3)3·6H2O (Acros Organics, 99.99%), Dy(NO3)3·5H2O (Alfa Aesar, 99.99%), Ni(NO3)2·6H2O (Alfa Aesar, 99.9985%), HNO3 solution (Ricca Chemicals, 20% v/v), and DI water (18.2 MΩ·cm). Synthesis of ETS-10. Impurity-free ETS-10 was synthesized exactly according to a previous report.19 In brief, a prestirred TiO2 and water dispersion was added to a prestirred SiO2, NaOH, KOH, and water solution. HCl was then added, and the mixture was stirred for 30 min. The obtained gel was transferred to a Teflon autoclave and statically heated to 230 °C for 3 days. The resultant mixture was cooled to room temperature and washed with DI water until the pH of the supernatant was reduced to ∼10. The solid precipitate was dried at 70 °C. Ion Adsorption Procedure. Calculated amounts of M(NO3)x·yH2O salt (M = Y, Nd, Eu, Tb, Dy, and Ni) were dissolved in 20 mL of DI water to obtain solutions of the desired initial ion concentrations (Ci): 0.25 mmol/L (actual concentration: 0.25 ± 0.01 mmol/L), 0.5 mmol/L (actual concentration: 0.50 ± 0.01 mmol/L), 1.5 mmol/L (actual concentration: 1.51 ± 0.02 mmol/L), 3 mmol/L (actual concentration: 3.02 ± 0.02 mmol/L), 5 mmol/L (actual concentration: 5.01 ± 0.08 mmol/L), 8 mmol/L (actual concentration: 8.07 ± 0.11 mmol/L), 10 mmol/L (actual concentration: 10.05 ± 0.13 mmol/L), and 13 mmol/L (actual concentration: 13.12 ± 0.18 mmol/L). For convenience, we will write the desired concentration values and not the actual concentrations henceforth. The pH of the solution was measured using a Fisherbrand accumet XL200 meter, and HNO3 was added to achieve a starting pH of 3 ± 0.2. ETS-10 (0.1 g) was dispersed in the obtained solution and stirred at room temperature for 2 h. The dispersion was centrifuged, and the supernatant was collected. Elemental analysis was performed on the supernatant to quantify the equilibrium metal concentration after the adsorption experiment. The metal-exchanged precipitate of ETS-10 was dried at 70 °C and collected for further analysis. Batch experiments to test the competitive adsorption of Ni2+ and Nd3+ ions on ETS-10 were performed in the exact same way mentioned above. The initial Ni2+ ion concentrations (Ci[Ni]) were 5, 8, 10, and 13 mmol/L, and the desired initial (Ni/Nd)initial molar ratios were 1 (actual ratio: 1.00 ± 0.02) and 12 (actual ratio: 12.10 ± 0.22). Batch adsorption experiments for the competitive adsorption of Nd3+ and Dy3+ ions on ETS-10 were performed in the exact same way as those for Ni2+ and Nd3+ mixture solutions. The desired initial (Nd/ Dy)initial molar ratios were 1 (actual ratio: 1.01 ± 0.01) and 12

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RESULTS AND DISCUSSION Powder XRD patterns of the as-synthesized and metaladsorbed ETS-10 (10 mmol/L initial ion concentration, Ci) samples are shown in Figure 1 and Figure S1. The as-

Figure 1. Powder XRD patterns of as-synthesized and single-metalion-adsorbed ETS-10 (10 mmol/L initial ion concentration, Ci).

synthesized ETS-10 powder is free of impurities, as observed from the diffraction pattern. No noticeable major changes are observed in the patterns after ion adsorption, suggesting that the titanosilicate ETS-10 crystal structure is stable under the acidic conditions used to test the ion adsorption capacity. The BET surface area (282.15 m2/g) and t-plot micropore volume (0.12 cm3/g) of as-synthesized ETS-10 are comparable to those reported in the literature (Figure S2).20 The ETS-10 particles are square bipyramidal with an average particle size of approximately Nd3+ ≈ Eu3+ > Tb3+ ≈ Ni2+ > Dy3+. Ce C 1 = e + Qe Qm Q mKL log(Q e) = RL =

(1)

log(Ce) + log(KF) n

1 1 + KLCi

(2)

(3)

The differences in the single-ion adsorption capacity (Qm), favorability (RL), and fitting parameter (KL) for the adsorption of Nd3+, Dy3+, and Ni2+ ions on ETS-10, as observed above, were further exploited in the separation of these ions from the Ni−Nd and Nd−Dy dilute aqueous mixtures usually generated during the recycling of NiMH batteries and NdFeB permanent magnets.6 The ion separation selectivity obtained in the solution after adsorption [(Ni/Nd)final/(Ni/Nd)initial] for Ni−Nd (Ni2+ and Nd3+ ions) and [(Nd/Dy)final/(Nd/ Dy)initial] for Nd−Dy (Nd3+ and Dy3+ ions) aqueous solutions at different initial solution ion concentrations (Ci[Ni] and Ci[Nd]) and initial molar ratiosis shown in Figure 4. As observed, the separation selectivity in the solution decreases on increasing the initial ion concentrations. A higher initial molar ratio, that is, (Ni/Nd)initial = 12 and (Nd/Dy)initial = 12, provides a better separation of ions in the solution; a solution separation selectivity of 31.5 (Ci[Ni] = 5 mmol/L) and 2 (Ci[Ni] = 13 mmol/L) is achieved for Ni−Nd aqueous solutions, whereas a solution separation selectivity of 3.69 (Ci[Nd] = 5 mmol/L) and 2.22 (Ci[Nd] = 13 mmol/L) is achieved for Nd−Dy aqueous solutions after adsorption experiments on ETS-10. The amount of metal ions remaining in the solution after adsorption on ETS-10 is shown in Figures S7 and S8. For (Ni/Nd)initial = 12 and Ci[Ni] = 5 mmol/L, almost all of the Nd ions (>98%) from the initial solution are removed and are now adsorbed on ETS-10; the solution is now highly concentrated in Ni2+ ions. The separation and adsorption of Nd3+ and Dy3+ ions using ETS-10 follows the same trend as the Ni2+ and Nd3+ ion mixture; however, a comparatively lower solution separation efficiency is achieved. Figures S9 and S10 provide information on the amount of ions adsorbed on ETS-10 during competitive ion separation experiments. These experiments provide conclusive proof that Ni−Nd aqueous solutions from NiMH batteries and Nd−Dy aqueous solutions from NdFeB permanent magnets could be recycled using ETS-10 for the recovery of these critical REE ions.

Figure 2. High-resolution images of as-synthesized ETS-10 nanoparticles: (a) SEM and (b) TEM.

lower than the REE hydroxide precipitate pH.21 A stirring time of 2 h was sufficient to attain ion adsorption equilibrium based on literature reports detailing the exchange of other heavy metal cations on ETS-10.20,22−25 Increasing the initial ion concentration (Ci) from 0.25 mmol/L increases the adsorption of ions on ETS-10, and clear differences in the capacity values can be seen for Ci > 5 mmol/ L (Figure S5). The experimental equilibrium ion adsorption data obtained on ETS-10 for these dilute solutions were fitted with two parametersthe Langmuir isotherm (eq 1) and the Freundlich isotherm (eq 2) models. Qm, KL, KF, and n are the isotherm fitting parameters, whereas Ce and Qe are the equilibrium concentration of ions in solution and the amount of ions adsorbed on ETS-10, respectively. On the basis of the calculated coefficient of determination (R2) values, compared with the Freundlich isotherm, the Langmuir isotherm model better represents the adsorption of heavy metal ions from acidic aqueous solutions on ETS-10 (Figure 3 and Table 1). The theoretical maximum adsorption capacity, Qm (mmol/g), predicted by the Langmuir isotherm fit of these ions on ETS10, follows the trend: Dy3+ > Tb3+ > Eu3+ > Ni2+ > Y3+ > Nd3+. The steepness of the isotherm at lower concentrations demonstrates the affinity of a particular ion toward ETS-10 and can be described by the parameter KL, where the values for these metal ions are significantly different from each other and follow the trend: Y3+ > Nd3+ > Eu3+ > Tb3+ > Ni2+ > Dy3+.26,27 This implies that ETS-10 is a better adsorbent for Nd3+ ions than for Ni2+ ions, and a separation can be achieved in a mixture. The separation factor, RL (eq 3), a variable describing

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CONCLUSIONS The adsorption of critical REE cations on ETS-10 titanosilicate in aqueous solutions is studied in this Research Note. The maximum adsorption capacity obtained by fitting the experimental data using the Langmuir isotherm shows that there is a distinction in the adsorption capacity, favorability, and fitting constants of these on ions and that they can be separated using ETS-10. The competitive separation of Nd3+ from Ni2+ ions and Dy3+ from Nd3+ ions in aqueous solutions 11123

DOI: 10.1021/acs.iecr.9b02623 Ind. Eng. Chem. Res. 2019, 58, 11121−11126

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Industrial & Engineering Chemistry Research

Figure 3. Two-parameter isotherm fits for metal ions adsorbed on ETS-10.

Table 1. Adsorption Isotherm Parameters for Ions Adsorbed on ETS-10 Langmuir isotherm

Freundlich isotherm 2

element

Qm (mmol/g)

KL (L/mmol)

R

Y Nd Eu Tb Dy Ni

0.5491 0.4723 0.6519 0.7206 0.7549 0.5731

37.40 10.01 9.708 5.198 4.162 4.984

0.9979 0.9988 0.9969 0.9961 0.9878 0.9914

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−1/n

KF (L

mmol

0.3838 0.3330 0.4462 0.4508 0.4805 0.3525

1−1/n

/g)

n

R2

3.945 4.543 4.042 3.439 3.945 3.606

0.7929 0.8825 0.9280 0.9316 0.8587 0.9576

DOI: 10.1021/acs.iecr.9b02623 Ind. Eng. Chem. Res. 2019, 58, 11121−11126

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Figure 4. Observed experimental ion separation selectivity in solution for (a) Ni2+ and Nd3+ ions (Ni−Nd aqueous streams; NiMH battery recycling) and (b) Nd3+ and Dy3+ ions (Nd−Dy aqueous streams; NdFeB permanent magnet recycling) by adsorption on ETS-10. Dashed lines are to guide the eye.

Materials for Renewable Energy” session in the Division of Energy and Fuels section of the 2019 ACS Spring National Meeting in Orlando. We acknowledge the financial support from the Department of Chemical Engineering and the Institute for Natural Gas Research (INGaR) at the Pennsylvania State University and the 3M Company (the 3M Non-Tenured Faculty Award). M.V. acknowledges support by the National Aeronautics and Space Administration (NASA) under grant no. NNX15AK06H issued through the PA Space Grant Consortium. J.B. acknowledges support from the Penn State Department of Physics and the National Science Foundation (DMR-1460920 and DMR-1420620, Penn State MRSEC RET (Research Experience for Teachers) Site). X.Z. acknowledges financial support from the John J. and Jean M. Brennan Clean Energy Early Career Professorship. Materials characterization was performed at the Materials Characterization Laboratory, which is a partner in the National Nanotechnology Infrastructure Network (NNIN) and the Materials Research Facilities Network (MRFN), supported by the U.S. National Science Foundation (award DMR-1420620).

is also studied, and there is clear separation and high separation selectivity obtained for these ions using ETS-10.

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ASSOCIATED CONTENT

* Supporting Information S

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.iecr.9b02623. Figure S1. Powder XRD patterns of as-synthesized, Ni2+ −Nd 3+ competitive-ion-adsorbed ETS-10 and Nd3+−Dy3+ competitive-ion-adsorbed ETS-10. Figure S2. N2 adsorption on as-synthesized ETS-10 sample. Figure S3. SEM image of Nd3+-adsorbed ETS-10 crystals and Ni2+-adsorbed ETS-10 crystals. Figure S4. Elemental maps of ions adsorbed on ETS-10 samples. Figure S5. Experimental data plot for adsorption of ions on ETS-10 with variation of initial ion concentration, Ci. Figure S6. Separation factor, RL, for adsorption of ions on ETS-10. Figure S7. Amount of metal ions in Ni−Nd aqueous solutions after adsorption experiments using ETS-10. Figure S8. Amount of metal ions in Nd−Dy aqueous solutions after adsorption experiments using ETS-10. Figure S9. Experimental data plot for adsorption of Ni2+ and Nd3+ ions on ETS-10 with variation of initial solution Ni2+ ion concentration, Ci[Ni], and (Ni/ Nd)initial molar ratio. Figure S10. Experimental data plot for adsorption of Nd3+ and Dy3+ ions on ETS-10 with variation of initial solution Nd3+ ion concentration, Ci[Nd], and (Nd/Dy)initial molar ratio (PDF)

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REFERENCES

(1) Binnemans, K.; Jones, P. T.; Blanpain, B.; Van Gerven, T.; Yang, Y.; Walton, A.; Buchert, M. Recycling of rare earths: a critical review. J. Cleaner Prod. 2013, 51, 1−22. (2) Dutta, T.; Kim, K.; Uchimiya, M.; Kwon, E. E.; Jeon, B.; Deep, A.; Yun, S. Global demand for rare earth resources and strategies for green mining. Environ. Res. 2016, 150, 182−190. (3) Tunsu, C.; Petranikova, M.; Gergoric, M.; Ekberg, C.; Retegan, T. Reclaiming rare earth elements from end-of-life products: A review of the perspectives for urban mining using hydrometallurgical unit operations. Hydrometallurgy 2015, 156, 239−258. (4) U.S. Department of Energy. Critical Materials Strategy, 2011. https://www.energy.gov/sites/prod/files/DOE_CMS2011_FINAL_ Full.pdf (accessed on April 13, 2019). (5) British Geological Survey, Natural Environment Research Council. Rare Earth Elements, 2011. https://www.bgs.ac.uk/ research/highlights/2010/rare_earth_elements.html (accessed on April 13, 2019). (6) Ferron, C. J.; Henry, P. A review of the recycling of rare earth metals. Can. Metall. Q. 2015, 54 (4), 388−394. (7) Izatt, S. R.; McKenzie, J. S.; Izatt, N. E.; Bruening, R. L.; Krakowiak, K. E.; Izatt, R. M. Molecular Recognition Technology: A

AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected]. ORCID

Xueyi Zhang: 0000-0002-3790-5116 Notes

The authors declare no competing financial interest.

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ACKNOWLEDGMENTS This contribution was identified by Lang Qin (The Ohio State University) as the Best Presentation in the “Emerging 11125

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Industrial & Engineering Chemistry Research Green Chemistry Process for Separation of Individual Rare Earth Metals. White Paper on Separation of Rare Earth Elements 2016, 1−12. (8) Jha, M. K.; Kumari, A.; Panda, R.; Rajesh Kumar, J.; Yoo, K.; Lee, J. Y. Review on hydrometallurgical recovery of rare earth metals. Hydrometallurgy 2016, 165 (1), 2−26. (9) Binnemans, K.; Jones, P. T.; Blanpain, B.; Van Gerven, T.; Pontikes, Y. Towards zero-waste valorization of rare-earth-containing industrial process residues: a critical review. J. Cleaner Prod. 2015, 99, 17−38. (10) Innocenzi, V.; De Michelis, I.; Kopacek, B.; Veglio, F. Yttrium recovery from primary and secondary sources: A review of main hydrometallurgical processes. Waste Manage. 2014, 34, 1237−1250. (11) Xie, F.; Zhang, T. A.; Dreisinger, D.; Doyle, F. A critical review on solvent extraction of rare earths from aqueous solutions. Miner. Eng. 2014, 56, 10−28. (12) Anastopoulos, I.; Bhatnagar, A.; Lima, E. C. Adsorption of rare earth metals: A review of recent literature. J. Mol. Liq. 2016, 221, 954−962. (13) Xiao, Y.; Huang, Li.; Long, Z.; Feng, Z.; Wang, L. Adsorption ability of rare earth elements on clay minerals and its practical performance. J. Rare Earths 2016, 34 (5), 543−548. (14) Lee, Y.; Yu, K.; Ravi, S.; Ahn, W. Selective Adsorption of rare earth elements over functionalized Cr-MIL-101. ACS Appl. Mater. Interfaces 2018, 10 (28), 23918−23927. (15) Jiang, L.; Zhang, W.; Luo, C.; Cheng, D.; Zhu, J. Adsorption toward trivalent rare earth element from aqueous solution by zeolite imidazolate frameworks. Ind. Eng. Chem. Res. 2016, 55 (22), 6365− 6372. (16) Oleksiienko, O.; Wolkersdorfer, C.; Sillanpaa, M. Titanosilicates in cation adsorption and cation exchange − A review. Chem. Eng. J. 2017, 317, 570−585. (17) Popa, K.; Pavel, C. C. Radioactive wastewaters purification using titanosilicate materials: State of the art and perspectives. Desalination 2012, 293, 78−86. (18) Anderson, M. W.; Terasaki, O.; Ohsuna, T.; Philippou, A.; MacKay, S. P.; Ferreira, A.; Rocha, J.; Lidin, S. Structure of the microporous titanosilicate ETS-10. Nature 1994, 367, 347−351. (19) Thakkar, J.; Yin, X.; Zhang, X. Ethylene oligomerization to select oligomers on Ni-ETS-10. ChemCatChem 2018, 10 (19), 4234− 4237. (20) Lv, L.; Su, F.; Zhao, X. S. Incorporation of hybrid elements into microporous titanosilicate ETS-10: An approach to improving its adsorption properties towards Pb2+. Microporous Mesoporous Mater. 2007, 101 (3), 355−362. (21) Moeller, T.; Kremers, H. E. Observations on Rare Earths. LI. An Electrometric study of the Precipitation of Trivalent Hydrous Rare Earth Oxides or Hydroxides. J. Phys. Chem. 1944, 48 (6), 395−406. (22) Lv, L.; Hor, M. P.; Su, F.; Zhao, X. S. Competitive adsorption of Pb2+, Cu2+, and Cd2+ ions on microporous titanosilicate ETS-10. J. Colloid Interface Sci. 2005, 287 (1), 178−184. (23) Choi, J. H.; Kim, S. D.; Noh, S. H.; Oh, S. J.; Kim, W. J. Adsorption behaviors of nano-sized ETS-10 and Al-substituted-ETAS10 in removing heavy metal ions, Pb2+ and Cd2+. Microporous Mesoporous Mater. 2006, 87 (3), 163−169. (24) Lv, L.; Tsoi, G.; Zhao, X. S. Uptake Equilibria and Mechanisms of Heavy Metal Ions on Microporous Titanosilicate ETS-10. Ind. Eng. Chem. Res. 2004, 43 (24), 7900−7906. (25) Zhao, G. X. S.; Lee, J. L.; Chia, P. H. Unusual Adsorption Properties of Microporous Titanosilicate ETS-10 toward Heavy Metal Lead. Langmuir 2003, 19 (6), 1977−1979. (26) Vijayaraghavan, K.; Padmesh, T. V. N.; Palanivelu, K.; Velan, M. Biosorption of nickel(II) ions onto Sargassum wightii: Application of two parameter and three-parameter isotherm models. J. Hazard. Mater. 2006, 133 (1−3), 304−308. (27) Davis, T. A.; Volesky, B.; Mucci, A. A review of the biochemistry of heavy metal biosorption by brown algae. Water Res. 2003, 37 (18), 4311−4330.

(28) Ho, Y. S.; Huang, C. T.; Huang, H. W. Equilibrium sorption isotherm for metal ions on tree fern. Process Biochem. 2002, 37, 1421− 1430. (29) Poots, V. J. P.; McKay, G.; Healy, J. J. Removal of basic dye from effluent using wood as an adsorbent. J. - Water Pollut. Control Fed. 1978, 50 (5), 926−935. (30) Weber, T. W.; Chakravorti, R. K. Pore and solid diffusion models for fixed-bed adsorbers. AIChE J. 1974, 20 (2), 228−238.

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DOI: 10.1021/acs.iecr.9b02623 Ind. Eng. Chem. Res. 2019, 58, 11121−11126